Project Summary/Abstract Despite intensive national efforts to address childhood obesity, the epidemic persists. Recognizing the challenges, the National Institutes of Health (NIH) and the Institute of Medicine (IOM) have called for a systems-oriented approach to address childhood obesity. We hypothesize that among low-income, ethnically diverse overweight and obese children, aged 2-12 years, a systems approach to child obesity incorporating secondary prevention programs embedded within primary prevention will reduce body mass index (BMI) z-scores compared to primary prevention alone. Intervention strategies will be adapted from the portfolio of evidence-based programs developed by study investigators. An assets-based assessment will be conducted with research and community partners in disadvantaged neighborhood catchment areas in Austin and Houston;data will inform integration of intervention strategies and provide a structure for program sustainability. Our specific study aims are: Aim 1: To implement and evaluate a primary prevention obesity program in low-income, ethnically diverse catchment areas in Austin and Houston. Baseline and 2-year follow-up data on the prevalence of child overweight, risk factors, and the availability of healthcare services and community programs will be collected in 2 demonstration (n=1614) and 2 control catchment areas (n=1614). Parent, child and community data will provide matched comparison data to assess the efficacy of the primary prevention intervention. Aim 2: To implement and evaluate the efficacy of a systems approach to child obesity on reducing obesity by embedding a 12-month family-based secondary prevention program within the community primary prevention program. The secondary prevention weight management program will be conducted with overweight/obese children and their families in the primary prevention catchment areas. Families of overweight/obese children (total n=576), aged 2-12 years, will be randomly assigned to either the 12-month secondary prevention program (experimental) or prevention program alone (control), stratified by age (2-5, 6-8, and 9-12 y). Outcomes include child BMI z-score, quality of life measures, and program use indicators. Aim 3: To quantify the incremental cost-effectiveness of the 12-month family-based secondary prevention program relative to primary prevention alone for child obesity. Activity Based Costing methods will be used to quantify the incremental cost of delivering the secondary prevention program relative to primary prevention. Public Health Relevance: If this research trial is proven efficacious and cost-effective, the demonstration project could be disseminated widely to address obesity among underserved, at risk children. Program sustainability will be ensured through active involvement of community partners within healthcare, childcare, schools and community sectors.